Composite high frequency component and mobile commmunication device including the same

ABSTRACT

The invention provides a composite high frequency component constituting a part of a microwave circuit having plural signal paths corresponding to their respective frequencies, comprising: a diplexer for coupling transmitting signals from the plural signal paths for transmission and distributing receiving signals into said plural signal paths for reception; plural high frequency switches for separating the plural signal paths into a transmission section and a reception section, respectively; plural filters introduced in the signal paths; said diplexer, said high frequency switch, and said filters being integrated into a ceramic multi-layer substrate formed by lamination of plural ceramic sheet layers. According to the above described composite high frequency component, the diplexer, the high frequency switches, and the filters which constitute the composite high frequency component are integrated into the ceramic multi-layer substrate formed by lamination of plural ceramic sheet layers. Thus, the matching and adjustment between the diplexer and the high frequency switches can be easily performed. It is unnecessary to provide a matching circuit for matching and adjusting the diplexer and the high frequency switches, and moreover, the high frequency switches and the filters.

BACKGROUND OF THE INVENTION

[0001] 1. Filed of the Invention

[0002] The present invention relates to a composite high frequencycomponent and a mobile communication device including the same, and moreparticularly to a composite high frequency component which can be usedin plural different mobile communication systems and a mobilecommunication device including the same.

[0003] 2. Description of the Related Art

[0004] At present, in Europe, as a mobile communication device, a dualband portable telephone has been proposed which can be operated inplural frequency bands, for example, DCS (Digital Cellular System)employing the 1.8 GHz band, and GSM (Global System for MobileCommunications) operative in the 900 MHZ band.

[0005]FIG. 14 is a block diagram showing a part of the configuration ofa dual band portable telephone as a conventional mobile communicationdevice, illustrating an example of the combination of DCS in the 1.8 GHzband and GSM in the 900 MHZ band. The dual band portable telephone isequipped with an antenna 1, a diplexer 2, and two signal paths, namely,the DCS system 3 and the GSM system 4.

[0006] The diplexer 2, for transmission, performs the function ofcoupling transmitting signals from the DCS system 3 or GSM system 4, andfor reception, does that of distributing received signals to the DCSsystem 3 or GSM system 4. The DCS system 3 is composed of a highfrequency switch 3 a for separating its transmission section Txd and itsreception section Rxd, and a notch filter 3 b for attenuating second andthird harmonics of DCS. The GSM system 4 is composed of a high frequencyswitch 4 a for separating its transmission section Txg and its receptionsection Rxg, and a notch filter 4 b for attenuating third harmonics ofGSM.

[0007] The high frequency switches 3 a and 4 a are separately providedwith controlling power supplies Vc 61 and Vc 62 for on-off controllingthe switches, respectively.

[0008] Hereinafter, the operation of the dual band portable telephonewill be described in reference to the case that the DCS system 3 is usedas an example. For transmission, with the high frequency switch 3 a, thetransmission section Txd is turned on, and a transmitting signal fromthe transmission section Txd is fed to the notch filter 3 b. Thetransmitting signal, passed through the notch filter 3 b, iswave-combined in the diplexer 2, and sent through the antenna 1. On theother hand, for reception, a receiving signal, received through theantenna 1, is wave-separated in the diplexer 2. The receiving signalform the antenna 1 is fed to the notch filter 3 b. With the highfrequency switch 3 a, the reception section Rxd is turned on, so thatthe receiving signal is fed through the notch filter 3 b to thereception section Rxd. In the case that the GSM system 4 is used, thetransmission and reception are carried out by similar operation.

[0009] Further, in Europe, as a mobile communication device, a tripleband portable telephone has also been proposed which can be operated inplural frequency bands, for example, by DCS (Digital Cellular System)and PCS (Personal Communication Services) which can be operated in the1.8 GHz band, and GSM (Global System for Mobile Communications)operative in the 900 MHZ band.

[0010]FIG. 15 is a block diagram showing the front end portion of aconventional triple band portable telephone as an example. In this case,as the first and second communication systems operative at adjacentfrequencies, DCS and PCS using the 1.8 GHz band, and also, as the thirdcommunication system applicable at a different frequency from the firstand second communication systems, GSM operative in the 900 MHZ band areemployed, respectively.

[0011] The front end portion of the triple band portable telephone isprovided with an antenna 1 a, a diplexer 2 a, first through third highfrequency switches 3 a through 5 a, and first and second filters 6 a and7 a. The diplexer 2 a has the function of coupling transmitting signalsby DCS, PCS, or GSM in the case of transmitting, and distributingreceiving signals to DCS, PCS, or GSM in the case of receiving. Thefirst high frequency switch 3 a switches the transmission section sideof DCS and PCS to the reception section side of DCS and PCS and viceversa. The second high frequency switch 4 a has the function ofswitching the reception section Rxd side of DCS to the reception sectionRxp side of PCS and vice versa. The third high frequency switch 5 a hasthe function of switching the transmission section Txg side of GSM tothe reception section Rxg side thereof and vice versa. The first filter6 a has the function of passing transmitting—receiving signals by DCSand PCS and attenuating second and third harmonics, and the secondfilter 7 a has the function of passing transmitting—receiving signals byGSM and attenuating the third harmonics.

[0012] Hereinafter, the operation of the triple band portable telephone,that is, first, the case of DSC will be described. In the case oftransmission, with the first high frequency switch 3 a, the transmissionsection Txdp common to that of PCS is turned on, so that a transmittingsignal from the transmission section Txdp is fed to the first filter 6a. The transmitting signal passed through the first filter 6 a iswave-associated in the diplexer 2 a and sent through the antenna 1 a. Inthe case of receiving, a receiving signal received through the antenna 1a is wave-separated in the diplexer 2 a. The receiving signal from theantenna 1 a is fed to the first filter 6 a which is on the DCS and PCSside. With the first high frequency switch 3 a, the reception sectionside is turned on so that the receiving signal passed through the firstfilter 6 a is fed to the second high frequency switch 4 a. With thesecond high frequency switch 4 a, the reception section Rxd of DCS isturned on, so that the receiving signal passed through the second highfrequency switch 4 a is fed to the reception section Rxd of DCS. In thecase of PCS used, the transmission and reception is performed by similaroperation.

[0013] Thereafter, the case of GSM will be described. In the case oftransmission, with the third high frequency switch 5 a, the transmissionsection Txg is turned on so that a transmitting signal from thetransmission section Txg is fed to the second filter 7 a. Thetransmitting signal passed through the second filter 7 a iswave-associated in the diplexer 2 a and sent through the antenna 1 a. Inthe case of receiving, a receiving signal received through the antenna 1a is wave-separated in the diplexer 2 a. The receiving signal from theantenna 1 a is fed to the second filter 7 a which is on the GSM side.With the third high frequency switch 5 a, the reception section Rxg isturned on, so that the receiving signal passed through the second filter7 a is fed to the reception section Rxg.

[0014] However, in the above-described dual band portable telephonewhich is one of conventional mobile communication devices, the antenna,the diplexer, and the high frequency switches and filters constitutingthe DCS system and the GSM system are discrete, and are mounted one byone on a circuit board. Accordingly, it is necessary to provide amatching circuit between the diplexer and the high frequency switches inorder to assure the matching, the attenuation, or the isolationcharacteristics. For this reason, the number of the components isincreased, causing the increase of the mounting area. As a result, it isnecessary to employ a large circuit board. This causes the trouble thatthe dual band portable telephone (mobile communication device) isincreased in size.

[0015] Further, in the above-described dual band portable telephonewhich is one of conventional mobile communication devices, the DCSsystem and the GSM system are on-off controlled by means of the twoseparate controlling power supplies only, connected separately to thetransmission sides of the high frequency switches. Thus, during thetransmission, the high frequency switches of the DCS system and the GSMsystem are differently operated, which causes the distortion problemwith respect to the off-side high frequency switch. Furthermore, it istroublesome that the control of the high frequency switches for thetransmission becomes complicate.

[0016] Further, in the above-described triple band portable telephonewhich is one of conventional mobile communication devices, the antenna,the diplexer, and also, the high frequency switches and the filtersconstituting the DCS system and GSM system are discrete, and mounted onone circuit board. Therefore in order to assure the matching, theattenuation, and the isolation characteristics of the respectiveelements, it is necessary to provide a matching circuit between thediplexer and the high frequency switches. Accordingly, the number of theelements is risen, bringing the increase of the mounting area, andthereby, the large circuit board is needed. Thus, there is the problemthat the size of the triple band portable telephone (mobilecommunication device) is large in size.

SUMMARY OF THE INVENTION

[0017] To overcome the above described problems, preferred embodimentsof the present invention provide a composite high frequency componentfor which a matching circuit is unnecessary and of which the circuit canbe miniaturized, and of which the distortion at transmission isinhibited, and the control of the transmission can be simplified, and amobile communication device including the same.

[0018] One preferred embodiment of the present invention provides acomposite high frequency component constituting a part of a microwavecircuit having plural signal paths corresponding to their respectivefrequencies, comprising: a diplexer for coupling transmitting signalsfrom the plural signal paths for transmission and distributing receivingsignals into said plural signal paths for reception; plural highfrequency switches for separating the plural signal paths into atransmission section and a reception section, respectively; pluralfilters introduced in the signal paths; said diplexer, said highfrequency switch, and said filters being integrated into a ceramicmulti-layer substrate formed by lamination of plural ceramic sheetlayers.

[0019] According to the above described composite high frequencycomponent, the diplexer, the high frequency switches, and the filterswhich constitute the composite high frequency component are integratedinto the ceramic multi-layer substrate formed by lamination of pluralceramic sheet layers. Thus, the matching and adjustment between thediplexer and the high frequency switches can be easily performed. It isunnecessary to provide a matching circuit for matching and adjusting thediplexer and the high frequency switches, and moreover, the highfrequency switches and the filters.

[0020] Accordingly, the number of the elements can be reduced, andthereby, the circuit board for forming the microwave circuit having theplural signal paths can be miniaturized.

[0021] In the above described composite high frequency component, theplural filters may be connected to the transmission section sides whichare in the latter stage with respect to the high frequency switches.

[0022] According to the above described composite high frequencycomponent, the filters are connected to the transmission section sideswhich are in the latter stage with respect to the high frequencyswitches, respectively. Thus, the distortion of the transmitting signal,caused by the high power amplifiers arranged in the transmissionsections, can be attenuated. Thus, the insertion loss in the receptionsections can be improved.

[0023] In the above described composite high frequency component, eachof the plural filters may be a notch filter.

[0024] By using a notch filter, only the band area around the second andthird harmonics can be attenuated to thereby the deleterious effectthereof on a band-area around the fundamental wave is reduced.Therefore, an insertion loss around the band-area including thefundamental wave is reduced more compared with a low-pass filter and aband-pass filter which attenuates whole of the high harmonics.Accordingly, the loss of the composite high frequency component isimproved.

[0025] In the above described composite high frequency component, thediplexer may be composed of a first inductance element and a firstcapacitance element, each of the plural high frequency switches may becomposed of a switching element, a second inductance element, and asecond capacitance element, and each of the plural filters may becomposed of a third inductance element and a third capacitance element,and the switching elements, the first through third inductance elements,and the first through third capacitance elements may be contained in ormounted onto the ceramic multi-layer substrate and connected by means ofa connecting means formed inside the ceramic multi-layer substrate.

[0026] According to the above described composite high frequencycomponent, the diplexer comprises the first inductance elements and thefirst capacitance elements, each of the high frequency switches does theswitching elements, the second inductance elements, and the secondcapacitance elements, each of the filters does the third inductanceelement and the third capacitance elements, and moreover, they arecontained in or mounted onto the ceramic multi-layer substrate andconnected by means of a connecting means formed inside the ceramicmulti-layer substrate. Thus, the composite high frequency component canbe formed on one ceramic multi-layer substrate, and its miniaturizationcan be realized. In addition, the loss, caused by the wiring between theelements, can be improved. As a result, the overall loss of thecomposite high frequency component can be improved.

[0027] Further, the strip line electrodes to function as the inductorsare contained in or mounted onto the ceramic multi-layer substrate. Withthe wave-length shortening effect, the lengths of the strip lineelectrodes to function as the respective inductance elements can bereduced. Therefore, the insertion loss caused by these strip-lineelectrodes can be enhanced. The miniaturization of the composite highfrequency component and the reduction of the loss can be realized. As aresult, the miniaturization and the high qualities of the mobilecommunication device including the composite high frequency componentcan be also attained.

[0028] In the above described composite high frequency component, thesecond inductance elements constituting the plural high frequency yswitches may contain parallel trap coils and choke coils, and saidparallel trap coils and said choke coils may be formed of chip coils.

[0029] According to the above described composite high frequencycomponent, of the second inductance elements as the constituents of theplural high frequency switches, the choke coils and the parallel trapcoils are chip coils. Therefore, the high frequency switches can bedesigned so as to have a low loss, and the band can be widened.

[0030] Another preferred embodiment of the present invention provides amobile communication device including any one of the above describedcomposite high frequency component.

[0031] The above described mobile communication device employs thecomposite high frequency component which is small in size and has a lowloss. Therefore, the miniaturization and the high qualities of themobile communication device including the high frequency switch can beattained.

[0032] Yet another preferred embodiment of the present inventionprovides a composite high frequency component constituting a part of amicrowave circuit having plural signal paths corresponding to theirrespective frequencies, comprising: a diplexer for coupling transmittingsignals from the plural signal paths for transmission and distributingreceiving signals into said plural signal paths for reception; pluralhigh frequency switches for separating the plural signal paths into atransmission section and a reception section, respectively; pluralfilters introduced in the signal paths; each of said plural highfrequency switches including a first switching element connected to thetransmission section side and a second switching element connected tothe reception section side; and said plural high frequency switchesbeing on-off controllable with a first common controlling power supplyconnected to the plural high frequency switches on the transmissionsection sides thereof.

[0033] According to the above described composite high frequencycomponent, the plural high frequency switches are on-off controlled bymeans of the first common controlling power supply connected to thetransmission section sides. Therefore, for transmission, the plural highfrequency switches can be turned on at the same time, so that the higherharmonic distortion caused by the high frequency switches can bereduced, and the characteristics of the composite high frequencycomponent can be enhanced.

[0034] Further, the control of the high frequency switches can besimplified. Thus, the transmission and reception by the mobilecommunication device including the composite high frequency componentcan be simply controlled.

[0035] Moreover, as the first controlling power supply, only one powersupply is used. Thus, the wiring and arrangement on a substrate formounting the composite high frequency component such as printed boardcan be simplified. Thus, the miniaturization of the mounting board canbe realized. In addition, the mobile communication device including thecomposite high frequency component can be reduced in size.

[0036] Yet another preferred embodiment of the present inventionprovides a composite high frequency component constituting a part of amicrowave circuit having plural signal paths corresponding to theirrespective frequencies, comprising: a diplexer for coupling transmittingsignals from the plural signal paths for transmission and distributingreceiving signals into said plural signal paths for reception; pluralhigh frequency switches for separating the plural signal paths into atransmission section and a reception section, respectively; pluralfilters introduced in the signal paths; each of said plural highfrequency switches including a first switching element connected to thetransmission section side and a second switching element connected tothe reception section side; said plural high frequency switches beingon-off controllable with a first common controlling power supplyconnected to the plural high frequency switches on the transmissionsection sides thereof and a second common controlling power supplyconnected to the high frequency switches on the reception sides thereof.

[0037] According to the above described composite high frequencycomponent, the plural high frequency switches are on-off controlled bymeans of the first common controlling power supply connected to thetransmission section side and the second common controlling power supplyconnected to the reception section sides. Thus, for transmission, allthe first and second diodes of the plural high frequency switches can besecurely turned on, and the high frequency switches of the DCS and GSMsystems can be securely turned on at the same time. Accordingly, thehigher harmonic distortion during the transmission caused by the highfrequency switches can be further reduced, and the characteristics ofthe composite high frequency component can be further enhanced.

[0038] As the first and second controlling power supplies, only onepower supply is used, respectively. Thus, the wiring and arrangement onthe substrate for mounting the composite high frequency component suchas the printed board can be simplified, and the miniaturization of thesubstrate for mounting is realized. In addition, the mobilecommunication device including the composite high frequency componentcan be reduced in size.

[0039] In the above described composite high frequency component, theplural filters may be arranged between the plural high frequencyswitches and the transmission section sides, respectively.

[0040] According to the above described high frequency component, thefilters each are arranged between the high frequency switches and thetransmission section sides. Thus, the distortion of the transmittingsignal, caused by the high power amplifiers arranged on the transmissionsection sides, can be decreased. Accordingly, the insertion loss on thereception sides can be improved.

[0041] In the above described composite high frequency component, thediplexer, the plural high frequency switches, and the filters may beintegrated into a ceramic multi-layer substrate composed of pluralceramic sheet layers laminated together.

[0042] According to the above described composite high frequencycomponent, the diplexer, the high frequency switches, and the filterswhich constitute the composite high frequency component are integratedinto the ceramic multi-layer substrate formed by lamination of theplural ceramic sheet layers. Thus, the matching and adjustment betweenthe diplexer and the high frequency switches can be easily performed.Accordingly, it is unnecessary to provide a matching circuit between thehigh frequency switches and the filters.

[0043] Accordingly, the number of the elements can be reduced, whichenables the miniaturization of the circuit substrate on which themicrowave circuit including plural signal paths is formed.

[0044] In the above described composite high frequency component, thediplexer may be composed of first inductance elements and firstcapacitance elements, each of the plural high frequency switches may becomposed of the first switching element and the second switchingelement, second inductance elements, and second capacitance elements,and each of the plural filters may be composed of a third inductanceelement and third capacitance elements, and the first switching elementsand the second switching elements, the first through third inductanceelements, and the first through third capacitance elements may becontained in or mounted onto the ceramic multi-layer substrate andconnected by means of a connecting means formed inside the ceramicmulti-layer substrate.

[0045] According to the above described composite high frequencycomponent, the diplexer is constituted by the first inductance elementsand the first capacitance elements, each high frequency switch by theswitching elements, the second inductance elements, and the secondcapacitance elements, and each filter by the third inductance elementsand the third capacitance elements. Further, these elements arecontained in or mounted onto the ceramic multi-layer substrate, andconnected by means of a connecting means formed inside the ceramicmulti-layer substrate. Thus, the composite high frequency component canbe formed on one ceramic multi-layer substrate and can be miniaturized.In addition, the loss due to the wiring between the elements can bereduced. As a result, the overall loss of the composite high frequencycomponent can be improved.

[0046] With the wave-length shortening effect, the lengths of the stripline electrodes as the respective inductance elements can be reduced.Therefore, the insertion loss caused by these strip-line electrodes canbe enhanced. As a result, the miniaturization of the composite highfrequency component and the reduction of the loss can be realized.

[0047] In the above described composite high frequency component, thesecond inductance element constituting each of the plural high frequencyswitches may be formed of a choke coil, and the choke coil is integratedinto the ceramic multi-layer substrate.

[0048] According to the above described composite high frequencycomponent, the choke coils and the parallel trap coils of the secondinductance elements which constitute the plural high frequency switchesare chip coils. Thus, the high frequency switches can be designed so asto have a low loss, and moreover, its band can be widened.

[0049] Yet another preferred embodiment of the present inventionprovides a mobile communication device including any one of the abovedescribed composite high frequency component.

[0050] According to the above described mobile communication device, thecomposite high frequency component which is small in size and has a lesshigher harmonic distortion is employed. Therefore, the miniaturizationand the high performance of the mobile communication device includingthe composite high frequency component can be realized.

[0051] Yet another preferred embodiment of the present inventionprovides a composite high frequency component provided with a front endportion so formed as to correspond to first and second communicationsystems operative at adjacent frequencies, and a third communicationsystem operative at a frequency different from those of the first andsecond communication systems, comprising: a diplexer for couplingtransmitting signals from said first through third communication systemsin the case of transmission and for distributing receiving signals tosaid first through third communication systems in the case of reception;a first high frequency switch for separating the transmission section ofsaid first and second communication systems and the reception section ofthe first and second communication systems from each other; a secondhigh frequency switch for separating the reception section of the firstcommunication system and the reception section of the secondcommunication system from each other; a third high frequency switch forseparating the transmission section of said third communication systemand the reception section thereof from each other; a first filter forpassing transmission—reception signals of said first and secondcommunication systems; and a second filter for passingtransmission—reception signals of said third communication systems; andthe composite high frequency component being integrated into a ceramicmulti-layer substrate formed by lamination of plural ceramic sheetlayers.

[0052] According to the above described composite high frequencycomponent, the diplexer, the first through third high frequencyswitches, and the first and second filters, which constitute thecomposite high frequency component, are integrated into the ceramicmulti-layer substrate formed by lamination of plural ceramic sheetlayers, the matching, attenuation, or isolation characteristics can beassured. This makes it unnecessary to provide a matching circuit betweenthe diplexer and the first and third high frequency switches.

[0053] Thus, the number of the elements can be reduced, which enablesthe miniaturization of the composite high frequency component whichconstitutes the front end portion corresponding to the first throughthird communication systems.

[0054] In the above described composite high frequency component, atleast one of said first and second filters may be arranged in thepost-stage with respect to the high frequency switch.

[0055] According to the above described composite high frequencycomponent, the filters are arranged between the high frequency switchesand the transmission sections. Thus, the distortion of a transmittingsignal, caused by high power amplifiers formed in the transmissionsections can be reduced. Accordingly, the insertion loss of thereception sections can be improved.

[0056] In the above described composite high frequency component, thediplexer may comprise a first inductance element and a first capacitanceelement, each of the first through third high frequency switches maycomprise first and second switching elements, second inductanceelements, and second capacitance elements, and each of the first andsecond filters may comprise a third inductance element and a thirdcapacitance element; said first through third inductance elements, saidfirst through third capacitance elements, and said first and secondswitching elements being contained in or mounted onto said ceramicmulti-layer substrate and connected by a connecting means formed insidesaid ceramic multi-layer substrate.

[0057] According to the above described composite high frequencycomponent, the diplexer comprises the first inductance elements and thefirst capacitance elements, the first through third high frequencyswitches do the first and second switching elements, the secondinductance elements, and the second capacitance elements, respectively,the first and second filters do the third inductance elements and thethird capacitance elements, respectively, and these elements arecontained in or mounted onto the ceramic multi-layer substrate andconnected by means of a connecting means formed inside the ceramicmulti-layer substrate. Therefore, the composite high frequency componentcan be formed by use of one ceramic multi-layer substrate and furthercan be miniaturized. In addition, the loss caused by wirings between theelements can be improved. As a result, the overall loss of the compositehigh frequency component can be improved.

[0058] Further, with the wavelength shortening effects, the strip-lineelectrodes which function as the respective inductance elements can beshortened. Thus, the insertion losses due to these strip-line electrodescan be improved. As a result, the composite high frequency component canbe miniaturized, and the reduction of the loss can be realized.

[0059] Yet another preferred embodiment of the present inventionprovides a mobile communication system including any one of the abovedescribed composite high frequency component.

[0060] The above described mobile communication device contains thecomposite high frequency component which is small in size and has a lowloss. Accordingly, the mobile communication device having the compositehigh frequency component mounted thereto can be miniaturized andrendered high qualities.

[0061] Other features and advantages of the present invention willbecome apparent from the following description of the invention whichrefers to the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0062]FIG. 1 is a circuit diagram of the composite high frequencycomponent according to a first embodiment of the present invention.

[0063]FIG. 2 is an exploded perspective view of an essential part of thecomposite high frequency component shown in FIG. 1.

[0064]FIG. 3 is an upper side view of each of the first sheet layers (a)through the eighth sheet layers (h) which form the ceramic multi-layersubstrate of the composite high frequency component of FIG. 2.

[0065]FIG. 4 consists of an upper side view of each of the ninth sheetlayers (a) through the thirteenth sheet layers (e) and an lower sideview of the thirteenth sheet (f) which form the ceramic multi-layersubstrate of the composite high frequency component of FIG. 2.

[0066]FIG. 5 is a circuit diagram of a mobile communication deviceincluding the composite high frequency component according to a secondembodiment of the present invention.

[0067]FIG. 6 is a block diagram of a mobile communication deviceincluding the composite high frequency component according to a thirdembodiment of the present invention.

[0068]FIG. 7 is a circuit diagram of the composite high frequencycomponent according to a fourth embodiment of the present invention.

[0069]FIG. 8 is an exploded perspective view of an essential part of thecomposite high frequency component according to a fifth embodiment ofthe present invention.

[0070]FIG. 9 is a block diagram showing a part of the arrangement of themobile communication device including the composite high frequencycomponent of FIG. 1.

[0071]FIG. 10 is a circuit diagram of a composite high frequencycomponent according to a sixth embodiment of the present invention.

[0072]FIG. 11 is an exploded perspective view of an essential part ofthe composite high frequency component of FIG. 10.

[0073]FIG. 12 is a circuit diagram of the composite high frequencycomponent according to a seventh embodiment of the present invention.

[0074]FIG. 13 is a block diagram showing a part of the configuration ofa mobile communication device employing the composite high frequencycomponent of FIG. 10.

[0075]FIG. 14 is a block diagram showing a part of the arrangement of ageneral dual band portable telephone (mobile communication device).

[0076]FIG. 15 is a block diagram showing the configuration of the frontend portion of a general triple band portable telephone (mobilecommunication device).

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0077]FIG. 1 is a circuit diagram of a first embodiment of a compositehigh frequency component in accordance with the present invention. Acomposite high frequency component 10 is composed of the diplexer 2 andthe high frequency switch 3 a and the notch filter 3 b which make up theDCS system 3, and the high frequency switch 4 a and the notch filter 4 bwhich constitute the GSM system 4.

[0078] The antenna 1 is connected to a first port P11 of the diplexer 2,a first port P31 d of the notch filter 3 b of the DCS system 3 to asecond port P12, and a first port P31 g of the notch filter 4 b of theGSM system 4 to a third port P13, respectively.

[0079] In the DCS system 3, a first port P21 d of the high frequencyswitch 3 a is connected to a second port P32 d of the notch filter 3 b,the transmission section Txd to a second port P22 d of the highfrequency switch 3 a, and the reception section Rxd to a third port P23d, respectively.

[0080] Further, in the GSM system 4, a first port P21 g of the highfrequency switch 4 a is connected to a second port P32 g of the notchfilter 4 b, the transmission section Txg to a second port P22 g of thehigh frequency switch 4 a, and the reception section Rxg to a third portP23 g, respectively.

[0081] The diplexer 2 is composed of first inductors L11 and L12 whichare first inductance elements, and first capacitors C11 through C15which are first capacitance elements.

[0082] The first capacitors C11 and C12 are connected in series betweenthe first port P11 and the second port P12, and their node is groundedthrough the first inductor L11 and the first capacitor C13.

[0083] A parallel circuit comprising the first inductor L12 and thefirst capacitor C14 is connected between the first port P11 and thethird port P23. The parallel circuit on the third port P13 side isgrounded through the first capacitor C15.

[0084] The high frequency switch 3 a (4 a) is composed of first andsecond diodes D1 d and D2 d (D1 g and D2 g) which are first and secondswitching elements, second inductors L21 d through L23 d (L21 g throughL23 g) which are second inductance elements, and second capacitors C21 dthrough C23 d (C21 g through C23 g) which are second capacitanceelements. The second inductor L21 d (L21 g) is a parallel trap coil, anda second inductor L22 d (L22 g) is a choke coil.

[0085] The first diode D1 d (D1 g) is so connected between the firstport P21 d (P21 g) and the second port P22 d (P22 g) that its cathode ison the first port P21 d (P21 g) side. A series circuit comprising thesecond inductor L21 d (L21 g) and the second capacitor C21 d (C21 g) isconnected in parallel to the first diode D1 d (D1 g).

[0086] The second port P22 d (P22 g) side of the first diode D1 d (D1g), namely, its anode is grounded through the second inductor L22 d (L22g) and the second capacitor C22 d (C22 g). A first common controllingpower supply Vc1 for controlling the on-off of the high frequency switch3 a (4 a) is connected to the node between the second inductor L22 d(L22 g) and the second capacitor C22 d (C22 g).

[0087] Further, the second inductor L23 d (L23 g) is connected betweenthe first port P21 d (P21 g) and the third port P23 d (P23 g). Thesecond inductor L23 d (L23 g) on the third port P23 d (P23 g) side isgrounded through the second diode D2 d (D2 g) and the second capacitorC23 d (C23 g). The node between the anode of the second diode D2 d (D2g) and the second capacitor C23 d (C23 g) is grounded through a resistorRd (Rg).

[0088] The notch filter 3 b (4 b) is composed of a third inductor L31 d(L31 g) which is a third inductance element, and third capacitors C31 dand C32 d (C31 g and C32 g) which are third capacitance elements.

[0089] The third inductor L31 d (L31 g) is connected in series betweenthe first port P31 d (P31 g) and the second port P32 d (P32 g). Thethird capacitor C31 d (C31 g) is connected in parallel to the thirdinductor L31 d (L31 g).

[0090] The third inductor L31 d (L31 g) on the second port P32 d (P32 g)side is grounded through the third capacitor C32 d (C32 g).

[0091] Hereinafter, the operation of the composite high frequencycomponent 10 having the circuit arrangement of FIG. 1 will be described.First, if a transmitting signal of the DCS system 3 (1.8 GHz band) orthat of the GSM system 4 (900 MHZ band) is transmitted, a controllingvoltage 3V is applied from the first common controlling power supply Vc1connected to the transmission section Txd side of the high frequencyswitch 3 a of the DCS system 3 and the transmission section Txg side ofthe high frequency switch 4 a of the GSM system 4, so that the first andsecond diodes D1 d and D2 d of the high frequency switch 3 a of the DCSsystem 3, and the first and second diodes D1 g and D2 g of the highfrequency switch 4 a of the GSM system 4 are turned on, and thereby, atransmitting signal of the DCS system 3, passed through the highfrequency switch 3 a, the notch filter 3 b, and the diplexer 2, or atransmitting signal of the GSM system 4, passed through the highfrequency switch 4 a, the notch filter 4 b, and the diplexer 2, is sentthrough the antenna 1, respectively.

[0092] The transmitting signal from the DCS system 3 or the GSM system 4is fed only to the antenna 1, not to the GSM system 4 or the DCS system3, respectively, by means of the diplexer 2. Further, the second andthird harmonics of the DCS system 3 are attenuated in the notch filter 3b of the DCS system 3, while the third harmonics of the GSM system 4 isdone in the notch filter 4 b of the GSM system 4.

[0093] In the case that receiving signals for the DCS system 3 and theGSM system 4 are received, a controlling voltage of 0V is applied fromthe first common controlling power supply Vc1 connected to the highfrequency switch 3 a of the DCS system 3 on the transmission sectionTxd, and the high frequency switch 4 a of the GSM system 4 on thetransmission section Txg, so that the first and second diodes D1 d andD2 d of the high frequency switch 3 a of the DCS system 3 and the firstand second diodes D1 g and D2 g of the high frequency switch 4 a of theGSM system 4 are turned off, and thereby, the receiving signal for theDCS system 3 is given only to the reception section Rxd of the DCSsystem 3, while the receiving signal for the GSM system 4 only to thereceiving section Rxg of the GSM system 4.

[0094] The diplexer 2 prevents the receiving signal for the DCS system 3from being given to the GSM system 4 or one for the GSM system 4 frombeing applied to the DCS system 4.

[0095]FIG. 2 is an exploded perspective view of the essential part of acomposite high frequency component having the circuit arrangement ofFIG. 1. The composite high frequency component 10 contains a ceramicmulti-layer substrate 11. The ceramic multi-layer substrate 11, thoughnot shown in the figure, contains the first inductors L11 and L12, andthe first capacitors C11 through C15 which make up the diplexer 2, thesecond and third inductors L21 d, L23 d, and L31 d, and the second andthird capacitors C21 d, C22 d, C31 d, and C32 d which constitute thehigh frequency switch 3 a and the notch filter 3 b of the DCS system 3,and the second and third inductors L21 g, L23 g, and L31 g, the secondand third capacitors C21 g, C22 g, C31 g, and C32 g which constitute thehigh frequency switch 4 a and notch filter 4 b of the GSM system 4,respectively.

[0096] Further, on the surface of the ceramic multi-layer substrate 11,mounted are the first and second diodes D1 d and D2 d, the secondinductor (choke coil) L22 d, the second capacitor C23 d, and theresistor Rd which constitute the high frequency switch 3 a of the DCSsystem 3, and the first and second diodes D1 g and D2 g, the secondinductor (choke coil) L22 g, the second capacitor C23 g, and a resistorRg which make up the high frequency switch 4 a of the GSM system 4.

[0097] Further, twelve external terminals Ta through T1 are so formed asto elongate from the side face onto the bottom of the ceramicmulti-layer substrate 11 by screen printing or the like, respectively.The five external terminals Ta through Te of these external terminals Tathrough T1 are formed on one long-side side of the ceramic multi-layersubstrate 11, five external terminals Tg through Tk on the otherlong-side side of the ceramic multi-layer substrate 11, and theremaining two external terminals Tf and T1 on the opposite short-sidesides of the ceramic multi-layer substrate 11, respectively, by screenprinting or the like.

[0098] The external terminals Ta through T1 are used as the first portP11 of the diplexer 2, the second and third ports P22 d, P23 d, P22 g,and P23 g of the high frequency switches 3 a and 3 b, the terminalsconnected to the first controlling power supply Vc1 for the highfrequency switches 3 a and 3 b, and the ground terminals.

[0099] The ceramic multi-layer substrate 11 is covered with a metalliccap 12 in such a manner as that the first and second diodes D1 d, D1 g,D2 d, and D2 g, the second inductors L22 d and L22 g, the secondcapacitors C23 d and C23 g, and the resistors Rd and Rg are coated.

[0100] FIGS. 3(a) through 3(h) and FIGS. 4(a) through 4(f) are the upperand lower side views of the respective sheet layers constituting theceramic multi-layer substrate of the composite high frequency componentof FIG. 2. The ceramic multi-layer substrate 11 is formed by laminatingthe first through thirteenth sheet layers 11 a through 11 m made of aceramic containing as a major component barium oxide, aluminum oxide,and silica, in that order from the uppermost side, and firing thelaminate at a firing temperature of up to 1000° C.

[0101] Then, on the upper side of the first sheet layer 11 a, by screenprinting, formed are lands La for mounting the first and second diodesD1 d, D1 g, D2 d, and D2 g, the second inductors L22 d and L22 g, thesecond capacitor C23 d and C23 g, and the resistors Rd and Rg which areto be mounted on the surface of the ceramic multi-layer substrate 11.

[0102] On the upper sides of the third and tenth sheet layers 11 c and11 j, strip line electrodes SL1 through SL8 made of conductor layers areformed by screen printing or the like. Further, on the upper sides ofthe fourth through eighth and twelfth sheet layers 11 d through 11 h and11 l, capacitor electrodes Cp1 through Cp18 made of conductor layers areformed by screen printing or the like.

[0103] In addition, on the upper sides of the seventh, ninth, eleventhand thirteenth sheet layers 11 g, 11 i, 11 k, and 11 m, groundelectrodes G1 through G4 made of conductor layers are formed by screenprinting or the like. Further, on the lower side of the thirteenth sheetlayer 11 m (FIG. 4(f)), the external terminals Ta through T1 are formedby screen printing or the like.

[0104] For the first through eleventh sheet layers 11 a through 11 k intheir predetermined positions, provided are via holes electrodes VHathrough VHk for connecting the lands La, the strip line electrodes SL1through SL8, the strip line electrodes SL1 through SL8, and the groundelectrodes G1 through G4.

[0105] In this case, the first inductors L11 and L12 of the diplexer 2are formed with the strip line electrodes SL6 and SL7. Further, thesecond inductors L21 d and L23 d of the high frequency switch 3 a of theDCS system 3 are formed with the strip line electrodes SL2 and SL4, thethird inductor L31 d of the notch filter 3 b of the DCS system 3 withthe strip line electrode SL8 respectively.

[0106] Further, the second inductors L21 g and L23 g of the highfrequency switch 4 a of the GSM system 4 are formed with the strip lineelectrodes SL1 and SL3, and the third inductor L31 g of the notch filter4 b of the GSM system 4 with the strip line electrode SL5, respectively.

[0107] The first capacitor C11 of the diplexer 2 is formed with thecapacitor electrodes Cp6 and Cp9, the first capacitor C12 with thecapacitor electrodes Cp3 and Cp6, the first capacitor C13 with thecapacitor electrode Cp17 and the ground electrode G4, the firstcapacitor C14 with the capacitor electrodes Cp9 and Cp11, and the firstcapacitor C15 with the capacitor electrode Cp16 and the ground electrodeG4, respectively.

[0108] Further, the second capacitor C21 d of the high frequency switch3 a of the DCS system 3 is formed with the capacitor electrodes Cp5 andCp8, the second capacitor C22 d with the capacitor electrodes Cp5 andCp8, the second capacitor C22 d with the capacitor electrode Cp13 andthe ground electrode G2, respectively. The third capacitor C31 d of thenotch filter 3 b of the DCS system 3 is formed with the capacitorelectrodes Cp8 and Cp12, and the third capacitor C32 d with thecapacitor electrode Cp18 and the ground electrode G4, respectively.

[0109] The second capacitor C21 g of the high frequency switch 4 a ofthe GSM system 4 is formed with the capacitor electrodes Cp4 and Cp7,and the second capacitor C22 g with the capacitor electrode Cp13 and theground electrode G2, respectively. The third capacitor C31 g of thenotch filter 4 b of the GSM system 4 is formed with the capacitorelectrodes Cp7 and Cp10, and the third capacitor C32 g with thecapacitor electrode Cp15 and the ground electrode G4, respectively.

[0110] In the composite high frequency component of the firstembodiment, for the purpose of on-off controlling the high frequencyswitches of the DCS and GSM systems by means of the first commoncontrolling power supply connected to the transmission sides, the highfrequency switches of the DCS and GSM systems can be turned on at thesame time. Accordingly, the higher harmonic distortion with respect tothe high frequency switches during the transmission can be reduced,enhancing the characteristics of the composite high frequency component.

[0111] Since the control of the high frequency switches can besimplified, the transmission and reception of the mobile communicationdevice including the composite high frequency component can be simplycarried out.

[0112] In addition, since only one power supply is used as the firstcontrolling power supply, the wiring and arrangement on a substrate formounting the composite high frequency component such as a printsubstrate or the like is simplified. That is, the miniaturization of themounted board can be realized. In addition, the size of the mobilecommunication device including the composite high frequency componentcan be reduced.

[0113] When the diplexer, the high frequency switches, and the filterswhich constitute the composite high frequency component are integratedinto the ceramic multi-layer substrate formed by lamination of theplural ceramic sheet layers, the matching and adjustment between thediplexer and the high frequency switches can be easily performed.Accordingly, it is unnecessary to provide a matching circuit formatching and adjusting the diplexer and the high frequency switch. Thus,the miniaturization of the composite high frequency component can berealized. For example, one diplexer, two high frequency switches, andtwo filters could be so integrated as to have a size of 6.7 mm′ 5 mm′ 2mm.

[0114] The diplexer is constituted by the first inductors and the firstcapacitors, each high frequency switch by the diodes, the secondinductors, and the second capacitors; and the filter by the thirdinductors, and the third capacitors, and moreover, they are contained inor mounted onto the ceramic multi-layer substrate, and connected with aconnecting means formed inside the ceramic multi-layer substrate.Accordingly, the composite high frequency component can be configured byuse of the one ceramic multi-layer substrate, that is, it can beminiaturized. In addition, the loss, caused by the wiring between theelements can be improved. As a result, the loss of the overall compositehigh frequency component can be reduced.

[0115] The wave-length shortening effect enables the reduction of thelengths of the strip lines which function as the inductors. Therefore,the insertion losses of these strip line electrodes can be improved. Asa result, the miniaturization and the reduction in loss of the compositehigh frequency component can be achieved. Simultaneously, theminiaturization and high performance of the mobile communication deviceincluding the composite high frequency component can be realized.

[0116]FIG. 5 is a circuit diagram of the composite high frequencycomponent according to a second embodiment of the present invention. Acomposite high frequency component 20 x is different from the compositehigh frequency component 10 of the first embodiment (FIG. 1) in theconnection locations of the filter 3 bx of the DCS system 3 x and thefilter 4 bx of the GSM system 4 x.

[0117] More particularly, the filter 3 bx of the DCS system 3 x isconnected to the transmission section Txd side which is in the latterstage with respect to the high frequency switch 3 ax, and the filter 4bx of the GSM system 4 x to the transmission section side Txg which isin the latter stage with respect to the high frequency switch 4 ax,respectively.

[0118] In the composite high frequency component of the above describedsecond embodiment, each filter is connected to the transmission sectionside which is in the latter stage of the high frequency switch, thedistortion during the transmission, caused by a high power amplifierprovided in the transmission section can be attenuated by means of thefilter. Thus, the insertion loss on the reception section side can beimproved.

[0119]FIG. 6 is a circuit diagram of a third embodiment of the compositehigh frequency component of the present invention. The composite highfrequency component 30 is composed of the diplexer 2, a high frequencyswitch 31 a and the notch filter 3 b constituting the DCS system 3, anda high frequency switch 41 a and the notch filter 4 b constituting theGSM system 4.

[0120] The configurations of the diplexer 2, the notch filter 3 b of theDCS system 3, and the notch filter 4 b of the GSM system 4 are the sameas those of the composite high frequency component 10 of the firstembodiment of the FIG. 1.

[0121] The high frequency switch 31 a (41 a) is composed of the firstand second diodes D1 d (D1 g) and D2 d (D2 g) which are first and secondswitching elements, the second inductors L21 d through L23 d (L21 gthrough L23 g) which are second inductance elements, and the secondcapacitors C21 d through C23 d (C21 g through C23 g) which are secondcapacitance elements. The second inductor L21 d (L21 g) is a paralleltrap coil, and the second inductor L22 d (L22 g) is a choke coil.

[0122] The first diode D1 d (D1 g) is so connected between the firstport P21 d (P21 g) and the second port P22 d (P22 g) that its cathode ison the first port P21 d (P21 g) side. A series circuit comprising thesecond inductor L21 d (L21 g) and the second capacitor C21 d (C21 g) isconnected in parallel to the first diode D1 d (D1 g).

[0123] The second port P22 d (P22 g) side of the first diode D1 d (D1g), namely, its anode is grounded through the second inductor L22 d (L22g) and the second capacitor C22 d (C22 g). The first common controllingpower supply Vc1 for controlling the on-off of the high frequency switch31 a (41 a) is connected to the node between the second inductor L22 d(L22 g) and the second capacitor C22 d (C22 g).

[0124] Further, the second inductor L23 d (L23 g) is connected betweenthe first port P21 d (P21 g) and the third port P23 d (P23 g). Thesecond inductor L23 d (L23 g) on the third port P23 d (P23 g) side isgrounded through the second diode D2 d (D2 g) and the second capacitorC23 d (C23 g). To the node between the anode of the second diode D2 d(D2 g) and the second capacitor C23 d (C23 g), the second commoncontrolling power supply Vc2 for controlling the on-off of the highfrequency switch 31 a (41 a) is connected through the resistor Rd (Rg).

[0125] Hereinafter, the operation of the composite high frequencycomponent 20 having the circuit arrangement shown in FIG. 6 will be nowdescribed. First, in the case that a transmitting signal by the DCSsystem 3 (1.8 GHz band) or by the GSM system 4 (900 MHZ band) istransmitted, a controlling voltage of 3V is applied from the firstcommon controlling power supply Vc1 connected to the high frequencyswitch 31 a of the DCS system 3 and the high frequency switch 41 a ofthe GSM system 4 on the transmission section Txd and Txg sides, and acontrolling voltage of 0V is applied from the second common controllingpower supply Vc2 connected to the high frequency switch 31 a of the DCSsystem 3 and the high frequency switch 41 a of the GSM system 4 on thereception section Rxd and Rxg sides, so that the first and second diodesD1 d and D2 d of the high frequency switch 31 a of the DCS system 3 andthe first and second diodes D1 g and D2 g of the high frequency switch41 a of the GSM system 4 are securely turned on, and thereby, thetransmitting signal from the DCS system 3 is passed through the highfrequency switch 31 a, the notch filter 3 b, and the diplexer 2, or thetransmitting signal from the GSM system 4 is passed through the highfrequency switch 41 a. The notch filter 4 b, and the diplexer 2, andthen, sent through the antenna 1, respectively.

[0126] The transmitting signal from the DCS system 3 or the GSM system 4is fed only to the antenna 1, not to the GSM system 4 or the DCS system3, correspondingly, by means of the diplexer 2. Further, the second andthird harmonics of the DCS system 3 are attenuated in the notch filter 3b of the DCS system 3, while the third harmonics of the GSM system 4 isdone in the notch filter 4 b of the GSM system 4.

[0127] In the case that a receiving signal for the DCS system 3 or theGSM system 4 is received, a controlling voltage of 0V is applied fromthe first common controlling power supply Vc1 connected to the highfrequency switch 31 a of the DCS system 3 on the transmission sectionTxd side and the high frequency switch 41 a of the GSM system 4 on thetransmission section Txd side, and a controlling voltage of 3V isapplied from the second common controlling power supply Vc2 connected tothe high frequency switch 31 a of the DCS system 3 on the receptionsection Rxd side and the high frequency switch 41 a of the GSM system 4on the reception section Rxg side, so that the first and second diodesD1 d and D2 d of the high frequency switch 31 a of the DCS system 3 andthe first and second diodes D1 g and D2 g of the high frequency switch41 a of the GSM system 4 are securely turned off, and thereby, thereceiving signal for the DCS system 3 is given only to the receptionsection Rxd of the DCS system 3, while the receiving signal for the GSMsystem 4 only to the reception section Rxg of the GSM system 4.

[0128] The diplexer 2 prevents the receiving signal for the DCS system 3from being fed to the GSM system 4 and one for the GSM system 4 frombeing fed to the DCS system 4, respectively.

[0129] In the composite high frequency component of the above describedthird embodiment, the high frequency switches of the DCS and GSM systemsare on-off controlled by means of the first common controlling powersupply connected to the transmission section sides and the second commoncontrolling power supply connected to the reception section sides. Thus,for transmission, all the first and second diodes of the high frequencyswitches of the DCS and GSM systems can be securely turned on, and thehigh frequency switches of the DCS and GSM systems can be securelyturned off at the same time. Accordingly, the higher harmonic distortionof the high frequency switches, occurring during the transmission, canbe reduced, which enhances the characteristics of the composite highfrequency component.

[0130] In addition, as the first and the second controlling powersupplies, only one power supply is used, respectively. The wiring andarrangement on a substrate for mounting the composite high frequencycomponent such as a printed board or the like is simplified. That is,the miniaturization of the mounting board can be realized. In addition,the miniaturization of the mobile communication device including thecomposite high frequency component can be realized.

[0131]FIG. 7 is a circuit diagram of the composite high frequencycomponent according to a fourth embodiment of the present invention. Asregards a composite high frequency component 30, the arrangement andlocation of the notch filter 3 b constituting the DCS system 3 and thenotch filter 4 b constituting the GSM system 4 are different, comparedwith the composite high frequency component 10 (FIG. 1) of the firstembodiment.

[0132] More particularly, the notch filter 3 b of the DCS system 3 isarranged between the high frequency switch 3 a and the transmissionsection Txd, while the notch filter 4 b of the GSM system 4 between thehigh frequency switch 4 a and the transmission section Txg.

[0133] In the composite high frequency component of the above describedfourth embodiment, since each filter is arranged between the highfrequency switch and the transmission section, the distortion withrespect to the high power amplifier provided in the transmission sectioncan be reduced by means of the filter. Thus, the insertion loss on thereception section side can be improved.

[0134]FIG. 8 is an exploded perspective view showing the appearance ofan essential part of the composite high frequency component according toa fifth embodiment of the present invention. A composite high frequencycomponent 40, as compared with the composite high frequency component 10(FIG. 1) of the first embodiment, is different in that the parallel trapcoils L21 d and L21 g and the choke coils L22 d and L22 g, whichconstitute the high frequency switches 3 a and 4 a, respectively, areformed of chip coils, which are mounted on the ceramic multi-layersubstrate 11.

[0135] In the composite high frequency component of the above-describedfifth embodiment, the parallel coils and the choke coils of the highfrequency switches are formed with the chip coils having a high Q value.Therefore, the chip coils having the same shape and size can be used forplural systems operative in different frequency bands. Thus, themodification of the design, required because of the change of thefrequency band, can be easily carried out, and also, it can be performedin a short time. As a result, the manufacturing cost saving can berealized.

[0136] Since the Q values of the parallel trap coils and the choke coilsare increased, the pass band becomes wider, and the low loss can berealized.

[0137]FIG. 9 is a block diagram showing a part of the configuration of adual band portable telephone as the mobile communication device, inwhich the combination of DCS operative in the 1.8 GHz band with GSM inthe 900 MHZ band is shown as an example. The dual band portabletelephone 50 is equipped with the antenna 1 and the composite highfrequency component 10 (FIG. 1).

[0138] The antenna 1 is connected to the port P11 of the composite highfrequency component 10, and the ports P22 d, P23 d, P22 g, and P23 g tothe transmission section Txd of the DCS system, the reception sectionRxd of the DCS system, the transmission section Txg of the GSM system,and the reception section Rxg of the GSM system, respectively.

[0139] The above-described dual band portable telephone includes thecomposite high frequency component which is small in size and has lesshigh frequency distortion. Thus, the miniaturization and highperformance of the mobile communication device having the composite highfrequency component mounted thereto can be realized.

[0140] In the above first through fifth embodiments of the compositehigh frequency component, the dual band which is the combination of DCSwith GSM has been described. However, the dual band is not limited tothe combination of DCS with GSM. For example, the combination of PCS(Personal Communication Services) with AMPS (Advanced Mobile PhoneServices), that of DECT (Digital European Cordless Telephone) with GSM,that of PHS (Personal Handy-phone System) with PDC (Personal DigitalCellular), and so forth can be employed.

[0141] Further, the case that the signal path consist of the two systemshas been described. However, the present invention is advantageous aswell in the case that the signal path consists of at least threesystems.

[0142] Further, the above embodiment of the mobile communication devicedescribes the case that the composite high frequency component of FIG. 1is employed in the dual band portable telephone which is the mobilecommunication device. The present invention, which employs the compositehigh frequency components of FIGS. 5 through 8, respectively, isadvantageous as well.

[0143]FIG. 10 is a circuit diagram of a sixth embodiment of a compositehigh frequency component according to the present invention. A compositehigh frequency component 101 comprises a diplexer 2 a shown in the blockdiagram of FIG. 15, and first through third high frequency switches 3 athrough 5 a, first and second filters 6 a and 7 a, and constitutes apart of a front end portion corresponding to DCS (1.8 GHz band), PCS(1.8 GHz band), and GSM (900 MHZ band) which are first through thirdcommunication systems.

[0144] An antenna 1 a is connected to the first port P211 of thediplexer 2 a, the first port P611 of the first filter 6 a to the secondport P221, and the first port P711 of the second filter 7 a to the thirdport P231, respectively.

[0145] The first port P311 of the first high frequency switch 3 a isconnected to the second port P621 of the first filter 6 a. Thetransmission section Txdp common to DCS and PCS is connected to thesecond port P321 of the first high frequency switch 3 a, and the firstport P411 of the second high frequency switch 4 a to the third portP331, respectively.

[0146] The reception section Rxd of DCS is connected to the second portP421 of the second high frequency switch 4 a, and the reception sectionRxp of PCS to the third port P431, respectively.

[0147] Further, the first port P51 of the third high frequency switch 5a is connected to the second port P721 of the second filter 7 a, thetransmission section Txg of GSM to the second port P521 of the thirdhigh frequency switch 5 a, and the reception section Rxg of GSM to thethird port P531, respectively.

[0148] The diplexer 2 a is formed with first inductors L111 and L121which are first inductance elements, and first capacitors C111 throughC151 which are first capacitance elements.

[0149] The first capacitors C111 and C121 are connected in seriesbetween the first port P211 and the second port P221, and their node isgrounded through the first inductor L111 and the first capacitor C131.

[0150] A parallel circuit comprising the first inductor L121 and thefirst capacitor C141 is connected between the first port P211 and thethird port P231. The parallel circuit on the third port P231 side isgrounded through the first capacitor C151.

[0151] The first high frequency switch 3 a comprises first and seconddiodes D1 a and D2 a which are first switching elements, secondinductors L211 through L231 which are second inductance elements, andsecond capacitors C211 through C231 which are second capacitanceelements.

[0152] The first diode D1 a is so connected between the first port P311and the second port P321 that its cathode is on the first port P311side. A series circuit comprising the second inductor L211 and thesecond capacitor C211 is connected in parallel to the first diode D1 a.

[0153] The first diode D1 a on the second port P321 side, namely, itsanode is grounded through the second inductor L221 and the secondcapacitor C221. The node between the second inductor L221 and the secondcapacitor C221 is provided with a first controlling terminal Vc31.

[0154] Further, the second inductor L231 is connected between the firstport P311 and the third port P331, and the second inductor L231 on thethird port P331 side is grounded through the second diode D2 a and thesecond capacitor C231. The node between the cathode of the second diodeD2 a and the second capacitor C231 is provided with the secondcontrolling terminal Vc32 through the resistor R.

[0155] In this case, the second inductor L211 connected in parallel withthe first diode D1 a is a parallel trap coil, and the second inductorL221 is a choke coil.

[0156] The first filter 6 a comprises a third inductor L311 which is athird inductance element and third capacitors C311 and C321 which arethird capacitance elements.

[0157] The third inductor L311 is connected in series between the firstport P611 and the second port P621. The third capacitor C311 isconnected in parallel to the third inductor L311.

[0158] The third inductor L311 on the second port P621 side is groundedthrough the third capacitor C321.

[0159] Each of the second and third high frequency switches 4 a and 5 ahas the same arrangement as the first high frequency switch 3 a. Thesecond filter 7 has the same arrangement as the first filter 6 a.

[0160]FIG. 11 is an exploded perspective view of an essential part ofthe composite high frequency component having the circuit arrangementshown in FIG. 10. The composite high frequency component 101 contains aceramic multi-layer substrate 111. In the ceramic multi-layer substrate111, though not shown, contained are the first inductors L111 and L121,and the first capacitors C111 through C151 which make up the diplexer 2a, the second inductors L211, L231 and the second capacitors C211 andC221 of the first high frequency switch 3 a, the second inductors L211,L231 and the second capacitors C211, C221 of the second high frequencyswitch 4 a, the second inductors L211, L231 and the second capacitorsC211, C221 of the third high frequency switch 5 a, the third inductorL311 and the third capacitors C311, C321 of the first filter 6 a, andthe third inductor L311 and the third capacitors C311, C321 of thesecond filter 7 a.

[0161] On the surface of the ceramic multi-layer substrate 111, in theform of chip elements, mounted are the first and second diodes D1 a andD2 a, the second inductor L221 (choke coil), the second capacitors C231,and the resistor R which constitute the first high frequency switch 3 a,and the first and second diodes D1 a, D2 a, the second inductor L221(choke coil), the second capacitor C231, and the resistor R whichconstitute the second high frequency switch 5 a, and the first andsecond diodes D1 a, D2 a, the second inductor L221 (choke coil), thesecond capacitor C231 and the resistor R which constitute the third highfrequency switch 5 a.

[0162] Further, fourteen external terminals Ta through Tn are so formedas to elongate from the side face onto the bottom of the ceramicmulti-layer substrate 111 by screen printing or the like, respectively.Of the external terminals Ta through Tn, the six external terminals Tathrough Tf are formed on one long-side side of the ceramic multi-layersubstrate 111, the six external terminals Th through Tm on the otherlong-side side of the ceramic multi-layer substrate 111, and theremaining two external terminals Tg and Tn on the opposite short-sidesides of the ceramic multi-layer substrate 111, respectively, by screenprinting or the like.

[0163] The external terminals Ta through Tn function as the first portP211 of the diplexer 2 a, the second port P321 of the first highfrequency switch 3 a, the second and third ports P42, P43, P52, P53 ofthe second and third high frequency switches 4 a and 5 a, and the firstand second controlling terminals Vc311, Vc321. Vc411, Vc421, Vc511,Vc521 and the ground terminals of the first through third high frequencyswitches 3 a through 5 a.

[0164] Further, the ceramic multi-layer substrate 111 is covered with ametal cap 121 so as to coat the surface of the ceramic multi-layersubstrate 111. In this case, the metal cap and the external terminals Tgand Tn which are formed on the respective opposite short-side sides ofthe ceramic multi-layer substrate 11 and function as a ground terminal.

[0165] The operation of the composite high frequency component 101having the circuit arrangement shown in FIG. 10 will be now described.First, if a transmitting signal by DCS or PCS (1.8 GHz band) istransmitted, 1V is applied to the first controlling terminal Vc 311, and0V to the second controlling terminal Vc 321, respectively, in the firsthigh frequency switch 3 a, so that the first port P311 and the secondport P321 of the first high frequency switch 3 a are connected, andthereby, the transmitting signal by DCS or PCS is passed through thefirst high frequency switch 3 a, the first filter 6 a, and the diplexer2 a, and sent through the antenna 1 a. In this case, the first filter 6a allows the transmitting signal by DCS, PCS to pass therethrough andattenuates the second and third harmonics.

[0166] In the second and third high frequency switches 4 a and 5 a, 0Vis applied to the first controlling terminals Vc 411 and Vc 511, and 1Vto the second controlling terminals Vc 42 and Vc 52, so that the secondand third high frequency switches 4 a and 5 a are cut off.

[0167] Further, in the case that a transmitting signal by GSM (900 MHZband) is transmitted, 1V is applied to the first controlling terminal Vc511 and 0V to the second controlling terminal Vc521, respectively, inthe third high frequency switch 5 a, so that the first port P511 andsecond port P521 of the third high frequency switch 5 a are connected,and thereby, the transmitting signal by GSM is passed through the thirdhigh frequency switch 5 a, the second filter 7 a, and the diplexer 2 a,and sent through the antenna 1 a. In this case, the second filter 7 aallows the transmitting signal by GSM to pass and attenuates the thirdharmonics.

[0168] In the first and second high frequency switches 3 a and 4 a, 0Vis applied to the first controlling terminals Vc311 and Vc 411, and 1Vto the second controlling terminals Vc321 and Vc421, so that the firstand second high frequency switches 3 a and 4 a are cut off,respectively.

[0169] Further, in the case that a receiving signal by DCS is received,0V is applied to the first controlling terminal Vc311, and 1V to thesecond controlling terminal Vc321, respectively, in the first highfrequency switch 3 a, so that the first port P311 and the third portP331 of the first high frequency switch 3 a are connected. In the secondhigh frequency switch 4 a, 0V is applied to the first controllingterminal Vc411, and 1V to the second controlling voltage Vc421, so thatthe first port P411 and the third port P431 of the second high frequencyswitch 4 a are connected, and thereby, the receiving signal by DCSreceived through the antenna 1 a is passed through the diplexer 2 a, thefirst filter 6 a, and the first and second high frequency switches 3 aand 4 a, and fed to the reception section Rxd of DCS. In this case, thefirst filter 6 a allows the receiving signal by DCS to pass andattenuates the second and third harmonics.

[0170] In the third high frequency switch 5 a, 0V is applied to thefirst controlling terminal Vc511, and 1V to the second controllingterminal Vc521, respectively, so that the third high frequency switch 5a is cut off.

[0171] Further, in the case that the receiving signal by PCS isreceived, 0V is applied to the first controlling terminal Vc311 and 1Vto the second controlling terminal Vc321, respectively, in the firsthigh frequency switch 3 a, so that the first port P311 and the thirdport P331 of the first high frequency switch 3 a are connected, and inthe second high frequency switch 4 a, 1V is applied to the firstcontrolling terminal Vc411, and 0V to the second controlling terminalVc421, respectively, so that the first port P411 and the second portP421 of the second high frequency switch 4 a are connected, and thereby,the receiving signal by PCS received through the antenna 1 a is passedthrough the diplexer 2 a, the first filter 6 a, and the first and secondhigh frequency switches 3 a and 4 a, and fed to the reception sectionRxp of PCS. In this case, the first filter 6 a allows the receivingsignal by PCS to pass and attenuates the second and third harmonics.

[0172] In the third high frequency switch 5 a, 0V is applied to thefirst controlling terminal Vc511, and 1V to the second controllingterminal Vc521, respectively, so that the third high frequency switch 5a is cut off.

[0173] In the case that a receiving signal by GSM, 0V is applied to thefirst controlling terminal Vc511, and 1V to the second controllingterminal Vc521, respectively, in the third high frequency switch 5 a, sothat the first port P511 and the third port P531 of the third highfrequency switch 5 a are connected, and thereby, the receiving signalfor GSM, received through the antenna 1, is passed through the diplexer2 a, the second filter 7 a, and the third high frequency switch 5 a, andfed to the reception section Rxg of GSM. In this case, the second filter7 a allows the receiving signal by GSM to pass, and attenuates the thirdharmonics.

[0174] In the first and second high frequency switches 3 a and 4 a, 0Vis applied to the first controlling terminals Vc 311 and Vc411, and 1Vto the second controlling terminals Vc321 and Vc421, respectively, sothat the first and second high frequency switches 3 a and 4 a are cutoff.

[0175] In the composite high frequency component of the sixthembodiment, the diplexer, the first through third high frequencyswitches, and the first and second filters, which constitute thecomposite high frequency component, are integrated into the ceramicmulti-layer substrate formed by lamination of plural ceramic sheetlayers. Thus, the matching, attenuation, and isolation characteristicsof the respective elements can be assured, and thereby, it isunnecessary to provide a matching network between the diplexer and thefirst through third high frequency switches.

[0176] Accordingly, the composite high frequency component can beminiaturized. For example, the diplexer, the first through third highfrequency switches, and the first and second filters can be integratedinto the ceramic multi-layer substrate with a size of 6.3 mm′ 5 mm′ 2mm.

[0177] Further, the diplexer comprises the first inductors and the firstcapacitors. Each of the first through third high frequency switchescomprises the first and second diodes, the second inductors, and thesecond capacitors. Each of the first and second filters comprises thethird inductor and the third capacitors. They are contained in ormounted onto the ceramic multi-layer substrate, and connected by use ofa connecting means formed inside the ceramic multi-layer substrate.Thus, the composite high frequency component can be formed on oneceramic multi-layer substrate, and can be miniaturized. In addition, theloss caused by wiring between its elements can be improved. As a result,the overall loss of the composite high frequency component can bereduced.

[0178] Further, with the wavelength shortening effect, the lengths ofthe strip-line electrodes, which function as the inductors, can beshortened. Thus, the insertion loss, caused by these strip-lineelectrodes, can be improved. As a result, the miniaturization and lowloss of the composite high frequency component can be realized.Accordingly, the miniaturization and high qualities of the mobilecommunication device including the composite high frequency componentcan be simultaneously attained.

[0179]FIG. 12 is a block diagram of the composite high frequencycomponent according to a seventh embodiment of the present invention.The composite high frequency component 201 is different from thecomposite high frequency component 101 of the sixth embodiment (FIG. 10)in the arrangement locations of the first and second filters 6 a and 7a.

[0180] That is, the first filter 6 a is arranged between the first highfrequency switch 3 a and the transmission section Txdp common to DCS andPCS, and the second filter 7 a between the third high frequency switch 4a and the transmission section Txg of GSM.

[0181] In the above-described composite high frequency component of theseventh embodiment, since the filters are arranged between the highfrequency switches and the transmission sections, respectively. Thus, intransmission, distortions, caused by high-power amplifiers provided inthe transmission sections can be reduced by means of the filters,respectively. Thus, an insertion loss on the receiving side can beimproved.

[0182]FIG. 13 is a block diagram showing a part of the configuration ofa triple band portable telephone which is one of mobile communicationdevices, illustrating, as an example, a combination of DCS with PCSoperative in the 1.8 GHz band and GSM in the 900 MHZ band. The tripleband portable telephone 301 is provided with the antenna 1 a and thecomposite high frequency component 101 (FIG. 10).

[0183] The antenna 1 a is connected to the port P111 of the compositehigh frequency component 101, the transmission section Txdp common toDCS and PCS, the reception section Rxp of PCS, the reception section Rxdof DCS, the transmission section Txg of GSM, and the reception sectionRxg of GSM to the ports P321, P421, P431, P521, and P531, respectively.

[0184] The above-described triple band portable telephone employs thecomposite high frequency component which is small in size and has a lowloss. Thus, the mobile communication device having the composite highfrequency component mounted thereon can be miniaturized and renderedhigh qualities.

[0185] If the composite high frequency components 201 (FIG. 12) isemployed instead of the composite high frequency component 101, similareffects can be obtained.

[0186] While the invention has been particularly shown and describedwith reference to preferred embodiments thereof, it will be understoodby those skilled in the art that the forgoing and other changes in formand details may be made therein without departing from the spirit of theinvention.

What is claimed is:
 1. A composite high frequency component constitutinga part of a microwave circuit having plural signal paths correspondingto their respective frequencies, comprising: a diplexer for couplingtransmitting signals from the plural signal paths for transmission anddistributing receiving signals into said plural signal paths forreception; plural high frequency switches for separating the pluralsignal paths into a transmission section and a reception section,respectively; plural filters introduced in the signal paths; saiddiplexer, said high frequency switch, and said filters being integratedinto a ceramic multi-layer substrate formed by lamination of pluralceramic sheet layers.
 2. The composite high frequency componentaccording to claim 1, wherein the plural filters are connected to thetransmission section sides which are in the latter stage with respect tothe high frequency switches.
 3. The composite high frequency componentaccording to claim 1, wherein each of the plural filters is a notchfilter.
 4. The composite high frequency component according to claim 2,wherein each of the plural filters is a notch filter.
 5. The compositehigh frequency component according to claim 1, wherein the diplexer iscomposed of a first inductance element and a first capacitance element,each of the plural high frequency switches is composed of a switchingelement, a second inductance element, and a second capacitance element,and each of the plural filters is composed of a third inductance elementand a third capacitance element, and the switching elements, the firstthrough third inductance elements, and the first through thirdcapacitance elements are contained in or mounted onto the ceramicmulti-layer substrate and connected by means of a connecting meansformed inside the ceramic multi-layer substrate.
 6. The composite highfrequency component according to claim 5, wherein the second inductanceelements constituting the plural high frequency switches containparallel trap coils and choke coils, and said parallel trap coils andsaid choke coils are formed of chip coils.
 7. A mobile communicationdevice including the composite high frequency component according toclaim
 1. 8. A composite high frequency component constituting a part ofa microwave circuit having plural signal paths corresponding to theirrespective frequencies, comprising: a diplexer for coupling transmittingsignals from the plural signal paths for transmission and distributingreceiving signals into said plural signal paths for reception; pluralhigh frequency switches for separating the plural signal paths into atransmission section and a reception section, respectively; pluralfilters introduced in the signal paths; each of said plural highfrequency switches including a first switching element connected to thetransmission section side and a second switching element connected tothe reception section side; and said plural high frequency switchesbeing on-off controllable with a first common controlling power supplyconnected to the plural high frequency switches on the transmissionsection sides thereof.
 9. The composite high frequency componentaccording to claim 8 or 8, wherein the plural filters are arrangedbetween the plural high frequency switches and the transmission sectionsides, respectively.
 10. A composite high frequency component accordingto any one of claim 8, wherein the diplexer, the plural high frequencyswitches, and the filters are integrated into a ceramic multi-layersubstrate composed of plural ceramic sheet layers laminated together.11. A mobile communication device including the composite high frequencycomponent according to any one of claim
 8. 12. A composite highfrequency component constituting a part of a microwave circuit havingplural signal paths corresponding to their respective frequencies,comprising: a diplexer for coupling transmitting signals from the pluralsignal paths for transmission and distributing receiving signals intosaid plural signal paths for reception; plural high frequency switchesfor separating the plural signal paths into a transmission section and areception section, respectively; plural filters introduced in the signalpaths; each of said plural high frequency switches including a firstswitching element connected to the transmission section side and asecond switching element connected to the reception section side; saidplural high frequency switches being on-off controllable with a firstcommon controlling power supply connected to the plural high frequencyswitches on the transmission section sides thereof and a second commoncontrolling power supply connected to the high frequency switches on thereception sides thereof.
 13. The composite high frequency componentaccording to claim 12, wherein the plural filters are arranged betweenthe plural high frequency switches and the transmission section sides,respectively.
 14. A composite high frequency component according toclaim 12, wherein the diplexer, the plural high frequency switches, andthe filters are integrated into a ceramic multi-layer substrate composedof plural ceramic sheet layers laminated together.
 15. A composite highfrequency component according to claim 14, wherein the diplexer iscomposed of first inductance elements and first capacitance elements,each of the plural high frequency switches is composed of the firstswitching element and the second switching element, second inductanceelements, and second capacitance elements, and each of the pluralfilters is composed of a third inductance element and third capacitanceelements, and the first switching elements and the second switchingelements, the first through third inductance elements, and the firstthrough third capacitance elements are contained in or mounted onto theceramic multi-layer substrate and connected by means of a connectingmeans formed inside the ceramic multi-layer substrate.
 16. The compositehigh frequency component according to claim 15, wherein the secondinductance element constituting each of the plural high frequencyswitches is formed of a choke coil, and the choke coil is integratedinto the ceramic multi-layer substrate.
 17. A mobile communicationdevice including the composite high frequency component according toclaim
 12. 18. A composite high frequency component provided with a frontend portion so formed as to correspond to first and second communicationsystems operative at adjacent frequencies, and a third communicationsystem operative at a frequency different from those of the first andsecond communication systems, comprising: a diplexer for couplingtransmitting signals from said first through third communication systemsin the case of transmission and for distributing receiving signals tosaid first through third communication systems in the case of reception;a first high frequency switch for separating the transmission section ofsaid first and second communication systems and the reception section ofthe first and second communication systems from each other; a secondhigh frequency switch for separating the reception section of the firstcommunication system and the reception section of the secondcommunication system from each other; a third high frequency switch forseparating the transmission section of said third communication systemand the reception section thereof from each other; a first filter forpassing transmission—reception signals of said first and secondcommunication systems; and a second filter for passingtransmission—reception signals of said third communication systems; andthe composite high frequency component being integrated into a ceramicmulti-layer substrate formed by lamination of plural ceramic sheetlayers.
 19. The composite high frequency component according to claim18, wherein at least one of said first and second filters is arranged inthe post-stage with respect to the high frequency switch.
 20. Thecomposite high frequency component according to claim 18, wherein thediplexer comprises a first inductance element and a first capacitanceelement, each of the first through third high frequency switchescomprises first and second switching elements, second inductanceelements, and second capacitance elements, and each of the first andsecond filters comprises a third inductance element and a thirdcapacitance element; said first through third inductance elements, saidfirst through third capacitance elements, and said first and secondswitching elements being contained in or mounted onto said ceramicmulti-layer substrate and connected by a connecting means formed insidesaid ceramic multi-layer substrate.
 21. A mobile communication systemincluding the composite high frequency component according to claim 14.